The novel HSP90 inhibitor NVP-AUY922 shows synergistic anti-leukemic activity with cytarabine in vivo

Exp Cell Res. 2016 Jan 15;340(2):220-6. doi: 10.1016/j.yexcr.2015.12.017. Epub 2015 Dec 31.


HSP90 is a molecular chaperone essential for stability, activity and intracellular sorting of many proteins, including oncoproteins, such as tyrosine kinases, transcription factors and cell cycle regulatory proteins. Therefore, inhibitors of HSP90 are being investigated for their potential as anti-cancer drugs. Here we show that the HSP90 inhibitor NVP-AUY922 induced degradation of the fusion oncoprotein FOP2-FGFR1 in a human acute myeloid leukemia (AML) cell line, KG-1a. Concordantly, downstream signaling cascades, such as STAT1, STAT3 and PLCγ were abrogated. At concentrations that caused FOP2-FGFR1 degradation and signaling abrogation, NVP-AUY922 treatment caused significant cell death and inhibition of proliferation of KG-1a cells in vitro. In an animal model for AML, NVP-AUY922 administrated alone showed no anti-leukemic activity. However, when NVP-AUY922 was administered in combination with cytarabine, the two compounds showed significant synergistic anti-leukemic activity in vivo. Thus NVP-AUY922 and cytarabine combination therapy might be a prospective strategy for AML treatment.

Keywords: Cytarabine; HSP90; KG-1a leukemia; NVP-AUY922; Tyrosine kinase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology*
  • Cell Line, Tumor
  • Cytarabine / pharmacology*
  • Disease Models, Animal
  • Female
  • HSP90 Heat-Shock Proteins / metabolism*
  • Humans
  • Isoxazoles / pharmacology*
  • Leukemia / drug therapy
  • Leukemia / metabolism*
  • Male
  • Neoplasm Proteins / metabolism
  • Resorcinols / pharmacology*
  • Signal Transduction / drug effects*


  • 5-(2,4-dihydroxy-5-isopropylphenyl)-4-(4-morpholin-4-ylmethylphenyl)isoxazole-3-carboxylic acid ethylamide
  • Antineoplastic Agents
  • HSP90 Heat-Shock Proteins
  • Isoxazoles
  • Neoplasm Proteins
  • Resorcinols
  • Cytarabine